Experimental Investigation and Modelling of Bacterial Growth and Inactivation: E. coli Exposed to Laser-synthesized Silver Nanoparticles
| Autor: | Krce, Lucija |
|---|---|
| Přispěvatelé: | Aviani, Ivica, Bilušić, Ante, Krstulović, Nikša, Raguž, Marija |
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
silver nanoparticles
nano-bio interakcije mikroskopija atomskom silom udc:577(043.3) Biochemistry. Molecular biology. Biophysics bacterial growth NATURAL SCIENCES. Interdisciplinary Natural Sciences modeliranje bakterijskog rasta antibacterial activity srebrne nanočestice udc:53(043.3) Young modulus reaktivne kisikove vrste nano-bio interactions logistic model PRIRODNE ZNANOSTI. Interdisciplinarne prirodne znanosti reactive oxygen species laser-synthesized nanoparticles atomic force microscopy modelling bacterial growth Physics brzina rasta E. coli način antibakterijskog djelovanja laserski sintetizirane nanočestice Youngov modul bakterijski rast bacterial growth E. coli growth rate logistic model silver nanoparticles antibacterial activity modelling bacterial growth laser-synthesized nanoparticles mode of antibacterial action nano-bio interactions reactive oxygen species atomic force microscopy Young modulus logistički model Biokemija. Molekularna biologija. Biofizika mode of antibacterial action growth rate Fizika antibakterijska aktivnost |
| Popis: | The aim of this thesis is to elaborate on the mode of antibacterial action by colloidal silver nanoparticles against Escherichia coli as a model organism. Two approaches were used to investigate the bactericidal mechanism of silver nanoparticles (AgNPs): experimental probing and modelling of the treated bacterial cell growth. AgNPs were synthesized by laser ablation in water and the obtained colloid was thoroughly characterized. An upgradable interaction-based growth model was developed to understand the effect of AgNPs on bacterial cell dynamics. The model explains untreated and AgNP-treated Escherichia coli growth in batch culture. Subsequently, fluorescence probing and atomic force microscopy and spectroscopy were used to experimentally study the AgNP bactericidal mechanism. This study shows that the mode of antibacterial action of silver nanoparticles includes penetration of AgNPs inside the cell/membrane, membrane permeabilization, reduction of the cell’s Young modulus and possible cell leakage while undistinguished reactive oxygen species level was detected inside lethally treated cells. Cilj ove teze je razjasniti način antibakterijskog djelovanja koloidnih nanočestica srebra na stanice Escherichia coli kao modelnog organizma. Istraživanje baktericidnog mehanizma srebrnih nanočestica provedeno je eksperimentalnim i teorijskim metodama kako bi se čim bolje opisao rast tretiranih bakterijskih stanica. Srebrne nanočestice su sintetizirane laserskom ablacijom u vodi, a dobiveni koloid je temeljito karakteriziran. Uveden je model rasta temeljen na interakcijama kako bi se razumio učinak nanočestica na dinamiku rasta bakterijskih stanica. Model objašnjava rast netretiranih i tretiranih bakterijskih stanica u tekućoj kulturi. Za eksperimentalno proučavanje baktericidnog mehanizma nanočestica korištene su fluorescentna spektroskopija te mikroskopija i spektroskopija atomskom silom. Istraživanje pokazuje da antibakterijsko djelovanje srebrnih nanočestica na bakterijske stanice uključuje njihov prodor unutar stanice/membrane, permeabilizaciju membrane, smanjenje Youngovog modula s vremenom te moguće istjecanje unutarstaničnog materijala, dok je inducirana razina reaktivnih kisikovih vrsta u smrtonosno tretiranim stanicama zanemariva. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|